Voice coil motors are commonly used to drive lenses in camera modules. The voice coil motor uses the electromagnetic drive principle of the energized coil and the magnet to drive the lens. The voice coil motor generally includes a base, a fixed barrel, a movable barrel, a coil and a magnet. One of the coil and the magnet is fixed to the fixed barrel, and the other is fixed to the outer wall of the movable barrel. The lens can be received in the movable barrel. To prevent electromagnetic leakage and electromagnetic interference, the voice coil motor typically has an electromagnetic shielding housing that receives the voice coil motor therein.
The voice coil motors are becoming thinner, the effective stroke of the voice coil motors are becoming higher, the thickness of the base is becoming thinner. As a result, the risk of the base and the housing breaking apart is becoming higher because the strength of the base decreases and the adhesion between the base and the housing is reduced as the base becomes thinner. So that the housing and the base may be easily separated when in use.